After John Isner won his biggest title to date at the Miami Open in April, he thanked his coach, and his family.

Then, by name, Clint Cordial. His chiropractor.

"Clint is my Chiropractor," he said to the crowd. "You know, I am almost 7 feet tall and 32-years old, it takes a lot to keep me on the court. It wasn't anything he's done [specifically] this week. It's what he's done through the course of six years we've been together. I have been very healthy for six years.

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"That is in large part to him adjusting, putting this machine on me, massage. It's everything. Physically at 32, I feel great, the best I have in a while. And that's in large part to him. There is a component of practicing and getting [to] the gym, but then the other part of the battle is taking care of yourself. That's what I do, and what he's done for me."

Currently ranked No. 11 in the world, and coming off his first Grand Slam semifinal appearance at Wimbledon, the now-33-year old is having a career year - and looks to keep it going with a quarterfinal showdown against Juan Martin del Potro on Tuesday. His team -- including Cordial who travels to every tournament with him -- has done their best to keep him healthy and focused throughout his run in Queens thus far.

We caught up with Cordial on Monday, to talk about his work with the American star, and how he's helped him prepare for his latest major run.

How does John Isner, nearly 7-feet tall and now 33, stay on the court? Photo by Matthew Stockman/Getty Images

ESPN: How did your partnership with John come to be?

Cordial: My brother Rory is a physical therapist and had worked with James Blake and Mardy Fish, and John was good friends with those guys. After that marathon match at Wimbledon [in 2010], he was looking for someone to come in and help, and I had just finished school. Rory said to John, Hey, you should check out my brother, I think you would really click personality wise." So we started working together on a tournament-by-tournament basis in 2012.

I started ahead of Indian Wells, and he ended up making the final in both singles and doubles, so it was good start to our relationship. I think it just gave both us confidence in each other. We then went on to Miami, which went OK, and then over to Europe. We just kept going, and here we are.

ESPN: If someone had said to you at that point that you would still be working together in 2018, would you have believed it?

Cordial: Yeah, funny you ask that. At the end of that first year, because we were just week-to-week, I was like "Hey, I would love to continue working with you. What are your thoughts?" I didn't know how the process went or anything, and he was like "I'd love to finish my career with you." I'm just a kid from Montana, so I don't really understand how the business stuff works but I took that to mean he was happy with what I was bringing to the team.

ESPN: Traveling from tournament to tournament, year after year, I would imagine you know each other pretty well at this point, how would you describe your relationship?

Cordial: He's a great guy. We've been together for so long. We know a lot about each other. It's a real friendship. Our personalities match up pretty good and yes, it's a fun atmosphere. However, there's a professionalism there too. You don't want to befriend someone so much that it becomes unprofessional and lose that respect to a degree. That's been something I've been very conscious of as I've worked with John.

It's tough being away from my family. [He has a four-year old son with his longtime girlfriend, and they are expecting another child this fall] That's the hardest part, but John is so good about that stuff. I can bring the family on the road to any tournament I want, you know, stuff like that. It doesn't have to be as hard as it sounds.

ESPN: How many players on the tour do you think have a full-time chiropractor with them?

Cordial: I would say the top 30 players all have a private one. It's a huge advantage for these players. The ATP provides physios, and they are great, but it's a first-come, first-served type system, so you're basically waiting in line, on their time. So if you're someone who is going deep into a tournament, you might not want to cater your time around that because you want to get as much rest as possible, and be on your own schedule that works best for you.

ESPN: John has been relatively healthy throughout his career, do you think that's in part to your work with him?

Cordial: I think both him and I have learned a lot as we've gotten older. I'm very diligent worker. I want to be the best I can be, so I'm constantly going to different seminars, courses, reading books and learning, talking to people, learning different techniques and stuff like that. That only helps him as well.

Now with that said, John is very professional and very committed to being as healthy as possible. He wants to be in shape, and just be the best he can be. He's done a lot with nutrition and diet, and he's so proactive and disciplined. The sports science field continues to evolve, just look at [Roger] Federer, or even Tom Brady, it's amazing how much older athletes can be and still be in peak condition. We are going to continue trying to learn and keep pushing the envelope.

ESPN: How much time per day do you typically spend with him?

Cordial: Honestly, all day. Take tomorrow for example, we'll drive to the courts tomorrow at 8:45 AM and we'll get him on the table. Then we'll do a warm-up, followed by a hitting warm-up on court. Then he'll come back and he'll stretch, and then we'll eat. Then we usually tailor to certain things he might need that day, like if something specific is bothering him. Then warm up again, and then do some more stuff on the table and then, finally, he'll play.

I watch the match from the stands. When it's over, we'll stretch, we'll eat, we'll tend to different things. Then we'll head to the hotel, do treatment. And then it's nighttime. So it's the whole day, all day. It's a pretty regimented schedule every day. I think most of these guys are OCD to a degree - they like their schedules and they like things a certain way. But it makes sense. It helps with their recovery, it helps with the performance, and so that's what we're just trying to do.

ESPN: What are some things you work on with him on a regular basis?

Cordial: Range of motion is one. We try to continually have good range of motion. We try to continually have muscle activation, and with range of motion, that means proper alignment. So I want his joints to be correctly aligned and moving correctly. The bones themselves, they seem okay, but are the muscles firing correctly? Let's say your shoulder joint, are all those muscles firing correctly to allow that joint to move in its correct range of motion, or is it gonna hiccup somewhere, in the hip or in the knee or in the ankle?

There's a lot of little checks I can do and a lot of little things I can do, and some maybe not so little. It's a flow that I have to come up with. It's blending different techniques through the years and utilizing my background as a chiropractor. And then it's always checking in with him and saying "How are you feeling? What's going on? Is there anything coming up? How's your foot? Is your knee bothering you?" The more he can tell me, the better I can do for him. He's so aware of what's going on with his body, and is vocal about it, so that really helps me do my job.

ESPN: He's obviously so tall [6'10"], does that change the way you work with him?

Cordial: Yeah, he's a big guy. It's a lot more time working with him, especially on the soft tissue stuff, and then the adjusting. Yeah, he's got long levers, heavy legs, stuff like that, but it's the same principles of the body. It's not in regards to that any different. It's just maybe more time, and it's part of the training that really might be a little bit different. A lot of times when you get these bigger individuals you'll see compensations a lot easier, which might be one of the reasons why we're starting to see a lot better results and better movement and ranges of motion with John. He's getting stronger in these different ranges of motion.

ESPN: It's interesting because it's often the big men, the centers, in basketball who often have the shortest careers, due to injuries ...

Cordial: Honestly, it's a big coup to him. He's been so proactive. Looking at his diet, when you start looking at different foods and different things you put in your body, I think you start looking at different inflammatory patterns that you can fall into. You get the tendonitis and then your muscles aren't firing correctly, and then you're joints deteriorate a little bit. That's the biggest thing I think that we've tried to work on is just allowing the muscles to protect the joints. In doing that you're just trying to get them to fire correctly. It seems to have worked pretty well.

ESPN: What was it like when he mentioned you on court in Miami after he won the title?

Cordial: I was so grateful to have that respect. I work my butt off with him. I thought that was great, it was very touching to me. And, it was his moment, it's all him out there on the court, so for him to share that with me and his coach, was pretty amazing.

Cordial: Well, he's obviously going to win. It's gonna be a hell of a battle and a great match. It's gonna be hot and it's gonna go back-and-forth, but I think it'll be fun. The atmosphere will be unbelievable. The Argentinian fans and the American crowd? It's going to be so loud, and just a great match.